In the days between Christmas and the New Year, much of the media world is in a silly state of pretend. A lot of people are nominally on the clock but have, in truth, sort of checked out. Anyway, because of that you get very silly posts like the one you are reading now, which is a write-up of a Business Insider write-up of a Reddit thread.
The internet—or those unlucky ducks on it this rainy December morning—is arguing about how dogs should wear pants.
So, look, the answer is obviously the one on the right.
Have a happy New Year.
Update 10:40am ET, Tuesday, December 29, 2015: Jared Keller at Maxim ran down the original creator of the image and has a nice post up examining how it came to tear the internet apart.